FAQ NS4 extractor tube

This FAQ contains frequently asked questions about the NS4 extractor tube that is installed in the VARIBOX FC. This FAQ is divided into four parts: the characteristics of the NS4 extractor tube, the availability, the NS4 coupler and the connection of the NS4 coupler to the NS4 extractor tube.

Characteristics NS4 extractor tube

What is a NS4 extractor tube?
A NS4 extractor tube is a tube in the VARIBOX FC that reaches the lowest point of the inner container. A coupler can be connected to the top of the NS4 extractor tube. The NS4 extractor tube is an option on the VARIBOX FC that allows product to be pumped out of the VARIBOX without opening the VARIBOX FC. This makes safe working with chemicals possible, even fumes and chemical product cannot escape from the VARIBOX FC. For certain dosing systems, a return connection is required, this is a standard feature on the top of the NS4 extractor tube.
Can fumes and product be released when using the NS4 extractor tube?
No, the VARIBOX FC with a NS4 extractor tube forms a closed system. After disconnection, the NS4 extractor tube and NS4 coupler automatically close. There is a possibility that the ends of the NS4 extractor tube and NS4 coupler can still be moist after disconnection, please avoid contact with this.
Do I have to open the screwcap to vent?
No, the screwcap of the VARIBOX FC has a built-in automatic aeration. The advantage is that the screwcap remains closed and no fumes can escape
How quickly can I pump out chemical product from the VARIBOX FC with the NS4 extractor tube?
The NS4 extractor tube has been developed for fine dosing. This means precise dosing of smaller volumes; up to a maximum of 50 litres per hour, depending on the viscosity of the product and the capacity of the pump installation. For quicker emptying of a VARIBOX FC the CDS extractor tube is more suitable. The CDS extractor has a capacity of 20 litres per minute. 
Does the NS4 extractor tube have a non-return valve?
Yes, the NS4 extractor tube is equipped with a non-return valve. When stationary, the product is held in the NS4 extractor tube and cannot flow back. When switching on, the pump will immediately draw in the product and there will be no air in the system. In the case of very long standstill time, air can gradually enter; the non-return valve does not give a 100% guarantee on sealing.
Does the NS4 extractor tube have a return connection?
Yes, there is a standard return connection on the NS4 extractor tube. A coupler can be connected to the return connection so that air, vapors or chemical product can be returned to the VARIBOX FC.
How long does the NS4 extractor tube last?
To ensure the safety of the VARIBOX FC with NS4 extractor tube, it is recommended to regularly check the NS4 extractor tube for possible damage. Replace the NS4 extractor tube or coupling if necessary.
How much product is left after emptying?
Very little product remains behind in de VARIBOX FC, because the NS4 extractor tube is in the lowest point of the inner container. Handling and transporting the empty VARIBOX FC is therefore safer. After emptying, approximately 0.1 liters remains in the VARIBOX FC. Less than 0.1 liter remains in the NS4 extractor tube itself. These quantities are based on water and will vary per chemical product.
Against which products is the NS4 extractor tube chemically resistant?
The NS4 extractor tube has been developed for use with a variety of chemicals. The NS4 extractor tube is resistant to most of chemicals, but it is very important to choose the correct version.
Which versions of NS4 extractor tube are available for the VARIBOX FC?
There are two versions NS4 extractor tubes; an EPDM version and a Viton version. The EPDM version has a stainless-steel spring. The Viton version has a Hastelloy spring. Tube, hose and housing are made of polyethylene. The couplings and base are made of polypropylene. The EPDM or Viton coupler can be distinguished by their color: a red jacket on the EPDM coupler and a gray jacket on the Viton version. If you have any specific questions about chemical resistance, please contact us.

NS4 coupler

How do I see the difference between an EPDM or Aflas / Viton coupler?
It is important for safe use of the VARIBOX FC to use an EPDM NS4 coupler on an EPDM NS4 extractor tube. On a Viton NS4 extractor tube only the Viton NS4 coupler may be used. The couplers can be distinguished by their color: a red jacket on the EPDM coupler and a gray jacket on the Viton version.
How can I see if a NS4 coupler is worn?
The NS4 coupler can wear from use. In case of visible wear, the NS4 coupler must be replaced. For example, the sealing ring (O-ring) can be damaged. In addition, the NS4 coupler can also fail due to chemical attack. Therefore, check the operation and closing of the coupler regularly.
What is the lifetime of a NS4 coupler?
The expected lifetime of the NS4 coupler is one year. Inspect the NS4 coupler regularly (i.e., annually or earlier if necessary) and replace if necessary. Chemical attack is highly dependent on the product, its concentration and temperature.

Connecting the NS4 coupler

How does the NS4 extractor tube work?
A liquid-tight connection is established when connecting the NS4 coupler. At the same time, the NS4 extractor tube and the NS4 coupler are opened, liquid can now flow freely. Fumes and chemical product cannot escape in this closed system.
How do I connect the NS4 coupler to the NS4 extractor tube?
To connect the VARIBOX FC with NS4 extractor tube, use a NS4 coupler that is attached to your system. Slide the NS4 coupler onto the NS4 extractor tube. Push the coupler until it clicks. Now the connection has been established and fluid can flow freely.
How do I disconnect an NS4 coupler?
To release the coupler, push the button on the coupler. The NS4 coupler can now be removed.
Can I disconnect the coupler at any time?
Yes, both the NS4 extractor tube and the NS4 coupler automatically close when disconnected. In this way you cannot forget to close the VARIBOX FC and no chemical product can flow back from the pump installation.
Can the extractor hose be stressed?
No, ensure that the extractor hose is not under tension. If the extractor hose is under tension, this can lead to leaks during connection or even tearing off a coupler. If necessary, move the hose or move the VARIBOX to prevent tension.

Availability NS4 extractor tube

Where can I order the NS4 extractor tube and/or the NS4 coupler?
The NS4 extractor tube and the NS4 coupler are available at RPC Promens. You can use the VARIBOX order form. To obtain this form please contact our customer service. You can mail to info@varibox-ibc.com or you can contact us by telephone on +31 570 660 711.

More information

Do you have any other specific questions regarding the NS4 extractor tube in the VARIBOX FC or do you want additional information please feel free to contact us by info@varibox-ibc.com or you can call us on (+31) 0570-660-711